Gracefully degrade summarization when an annotation is not a valid const expression (issue 28992)

pkg/analyzer/lib/src/summary/summarize_ast.dart

 // Copyright (c) 2016, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 library serialization.summarize_ast;
 
 import 'package:analyzer/dart/ast/ast.dart';
 import 'package:analyzer/dart/ast/token.dart';
 import 'package:analyzer/dart/ast/visitor.dart';
 import 'package:analyzer/dart/element/type.dart' show DartType;
@@ skipping 396 matching lines @@
       NodeList<Annotation> annotations) {
     if (annotations == null || annotations.isEmpty) {
       return const <UnlinkedExprBuilder>[];
     }
     return annotations.map((Annotation a) {
       // Closures can't appear inside annotations, so we don't need a
       // localClosureIndexMap.
       Map<int, int> localClosureIndexMap = null;
       _ConstExprSerializer serializer =
           new _ConstExprSerializer(this, localClosureIndexMap, null);
-      serializer.serializeAnnotation(a);
+      try {
+        serializer.serializeAnnotation(a);
+      } on StateError {
+        return new UnlinkedExprBuilder()..isValidConst = false;
+      }
       return serializer.toBuilder();
     }).toList();
   }
 
   /**
    * Serialize a [ClassDeclaration] or [ClassTypeAlias] into an [UnlinkedClass]
    * and store the result in [classes].
    */
   void serializeClass(
       AstNode node,
@@ skipping 989 matching lines @@
 /**
  * A [_TypeParameterScope] is a [_Scope] which defines [_ScopedTypeParameter]s.
  */
 class _TypeParameterScope extends _Scope {
   /**
    * Get the number of [_ScopedTypeParameter]s defined in this
    * [_TypeParameterScope].
    */
   int get length => _definedNames.length;
 }